-LRB- CNN -RRB- -- Two years ago , the Supreme Court upended the rules for campaign finance , unleashing a tsunami of unregulated , unrestricted and undisclosed spending that has , in effect , allowed donors to buy elections . The full impact of this decision is just now becoming clear , and it 's bad both for America 's businesses and for our democracy .

By a 5-4 majority , the Supreme Court affirmed that money is essentially speech -- a notion first addressed in Buckley v. Valeo in 1976 -- and it outlawed nearly all restrictions on independent spending by corporations or other groups , including unions , to influence elections . Such restrictions are unconstitutional violations of free speech , the court said , and are prohibited by the First Amendment .

You might expect business owners to welcome the elimination of these restrictions , but if so , you 're about to be surprised . A recent poll conducted by Lake Research found that 66 % of a random sample of 500 small-business owners believe the Citizens United decision was `` mostly bad '' or `` somewhat bad '' for small business . Since small businesses create 70 % of new jobs in the private sector , according to the Small Business Administration , their view should matter a lot .

The poll was commissioned by the American Sustainable Business Council , the Main Street Alliance , and Small Business Majority -- three groups that represent the views of small business and which have a combined membership of more than 100,000 small businesses nationwide . The poll tapped the views of 500 small-business owners nationwide , most of whom are not members of the organizations conducting the survey .

In addition to taking a dim view of Citizens United , 88 % of the small-business owners in the poll had a negative view of the role money plays in politics . -LRB- The margin of error in the poll is plus or minus 4.4 percentage points . -RRB-

Do small donations still matter in politics ? Tell us what you think .

Small-business owners believe in our market-based , capitalist system , which depends on open and robust competition .

Unlimited campaign spending undermines this competition , in three crucial ways .

First , allowing unlimited money into politics allows the past to hold the future hostage . Companies -LRB- and individuals who own them -RRB- with sufficient resources to sway elections often represent the industries and companies of the past , rather than the industries and companies that are creating the future .

The evidence on this is indirect , because since Citizens United was announced less than a year before the last federal election , its impact has not yet been fully felt or measured . However , we can gauge its future impact by looking at lobbying expenditures , for which multiyear data is widely available . For the period 2008-2011 , the computer and Internet industry -- a wellspring of innovation -- spent $ 458 million on lobbying , according to the Center for Responsive Politics , while the energy and natural resources industry spent more than three times as much : $ 1.55 billion . The ratio for election-related spending , post Citizens United , will likely be similar .

Second , allowing unlimited money in politics allows the big to achieve an unfair advantage over the small . This is ironic in light of the huge role small business plays in creating private sector jobs in America , even as some large corporations act as net destroyers of American jobs , when outsourcing and offshoring are factored in .

For example , this kind of money in politics gives power to the push by big companies to repatriate offshore profits , giving some big and profitable multinational corporations lower effective tax rates than the grocer on Main Street .

Moreover , unlimited contributions give major Wall Street firms the edge over community banks , because the big banks can win loan guarantees , taxpayer bailouts and deeply discounted borrowing rates that smaller banks ca n't touch .

Third , allowing unlimited money in politics allows companies to collect IOUs for special favors from presidential candidates -- particularly as a result of contributions made early in the election season , when a few million dollars can swing the result in a small state like New Hampshire .

America 's small-business owners embrace competition -- but they demand the competition be open , robust and vigorous . They do n't want to be whipped by big corporations that bought an unfair advantage from senators , congressional representatives and other elected officials . When that happens , it 's bad for business and America . Many solutions have been proposed , ranging from the Supreme Court reversing its decision , to legislation , to a constitutional amendment .

Momentum for change is growing , as candidates from both political parties learn what it 's like to have a campaign with broad public support crushed by a single individual with deep pockets who steps in to help the other side .

Citizens United is an assault on our economy , which is supposed to be based on vigorous , free and open competition . It 's time for us to reinvigorate our economy by getting government out of the protection racket , and preventing industries and companies from buying special favors . We must undo the damage wrought by Citizens United .

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The opinions expressed in this commentary are solely those of David Brodwin .

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David Brodwin says Citizens United ruling is bad for small businesses

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He says poll found that most small businesses do n't like role of money in politics

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He says that role favors old , moneyed industries , not new ones that drive innovation

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Brodwin : Campaign spending has un-American effect of stifling competition